The quality of municipal drinking water has continuously increased in the past decades. Yet, there is a growing need for detecting any upset conditions that would result in the introduction of harmful inorganic substances, such as lead, arsenic, cadmium, etc. Accurate and precise measurements of such are readily achieved in laboratories using expensive analytical equipment, such as ICP-MS. Not only is it expensive, the analysis requires a specially trained person and elaborate calibration and measurement procedures. This, therefore, is cost prohibitive for everyday home use by ordinary home owners.